Monitoring food and health news -- with particular attention to fads, fallacies and the "obesity" war

Summary of findings to date: Everything you can possibly eat or drink is both bad and good for you

"Let me have men about me that are fat... Yond Cassius has a lean and hungry look ... such men are dangerous." -- Shakespeare

Wednesday, July 20, 2011

Passive smoking harms hearing of teenagers

I abhor smoking but the report below is sheer nonsense. Working class people are more likely to smoke and have more hearing loss. That is all that they have detected. Yet another crappy study dedicated to condemning sidestream smoke

Teenagers exposed to second-hand smoke are twice as likely to suffer hearing loss, according to research. The findings add to the catalogue of health problems already attributed to second-hand smoke, including increased risks of asthma, heart disease and lung cancer.

Teens exposed to second-hand smoke were more likely to have ‘sensorineural’ hearing loss, which is usually caused by problems with the cochlea, the snail-shaped hearing organ of the inner ear. Scientists think passive smoking affects the blood supply to the area.

The damage caused makes it harder for the person to understand speech and has been linked to poor academic performance and disruptive behaviour in school.

Study author Dr Michael Weitzman, from New York University’s school of medicine, said: ‘It’s the type of hearing loss that usually tends to occur as one gets older, or among children born with congenital deafness.’

Dr Weitzman studied more than 1,500 teenagers aged 12 to 19. They were given extensive hearing tests along with blood tests for the chemical cotinine, a substance produced when the body breaks down nicotine. Those teens exposed to second-hand smoke, as measured by cotinine in their blood, were more likely to have sensorineural hearing loss than those who were not passive smokers.

Results of the study, published in journal Archives of Otolaryngology, which deals with head and neck surgery, also showed that more than four out of five affected were not aware of it.

Study co-author Dr Anil Lalwani, from the department of paediatrics at NYU’s school of medicine, said: ‘More than half of all children in the U.S. are exposed to second-hand smoke, so our finding has huge public health implications.’ He added: ‘Milder hearing loss is not necessarily noticeable. Thus, simply asking someone whether they think they have hearing loss is insufficient.’

Dr Weitzman added: ‘The consequences of mild hearing loss are subtle yet serious. ‘Affected children can have difficulty understanding what is being said in the classroom and become distracted. As a result, they may be labelled as troublemakers or misdiagnosed with ADHD.’

Recently I broke a strict personal rule by undergoing a complete private health screening. I’d always rigorously avoided such things, but this was obligatory for work. The battery of tests did the exact thing that I feared. It revealed a potential health problem I had never previously known — nor worried — about. The results showed I have high total cholesterol. Mine is 6.6mmol/l — the target is 5.1.

But I won’t be rushing to my family doctor. That’s because as a health journalist, I’ve seen the way the ‘danger’ threshold for cholesterol has been revised steadily down. Twenty years ago, I would have been well inside the ‘healthy’ category (back then you had to be over 7.6 to be considered unhealthy).

But am I being wise to ignore this warning? A new book by an expert on medical screening strongly vindicates my position. As author Dr H. Gilbert Welch explains: ‘There are many conditions that you can now be labelled with simply because you are on the wrong side of a number, not because you have any symptoms.’

Take diabetes — earlier this month it was revealed the NHS is lowering the threshold for diagnosing type 2 diabetes. As a result, the number of cases could rise by 20 per cent — a massive number. That means thousands more people will be treated for the condition without necessarily having any symptoms.

This is just another example of what Dr Welch describes as an ‘epidemic’ of overdiagnosis. In other words, physical abnormalities that will most likely lie dormant for the rest of our lives are being detected and treated as if you are actually ill.

Dr Welch, who is professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice in Virginia in the U.S., points the finger at our overzealous use of screening — blood tests and scans — which has caused millions of people to believe they are mortally sick when, in fact, they are perfectly healthy.

Worse, it has led countless numbers to take drugs and undergo surgery completely unnecessarily. As a result, they have suffered everything from botched removals of breast lumps to, says Dr Welch, medication-related car crashes.

At the heart of the problem is a change in medical culture over the past three decades. In the past, people didn’t go to the doctor when they were well — they tended to wait until they developed symptoms. And doctors didn’t encourage the healthy to seek care.

But that has changed. ‘Early diagnosis is the goal. People seek care when they are well,’ says Dr Welch.

‘But a patient who has been overdiagnosed cannot benefit from treatment. There’s nothing to be fixed — he or she will neither develop symptoms nor die from their condition — so the treatment is not needed. 'An overdiagnosed patient can only be harmed. And almost all treatments have the potential to do some harm.’

On top of this, there are changes to the thresholds that doctors use to judge if a person is ill or not. Dr Welch points to the example of diabetes. ‘The old rule, from when I was in medical school 30 years ago, was that if you had a blood-sugar level over 140, you had diabetes. But in 1997 experts changed the international definition. 'Now, if you have a reading of more than 126 you have diabetes. That little change turned millions of people into patients.’

As treatment is expanded to people with progressively milder abnormalities such as slightly high blood sugar, their potential to benefit from treatment becomes progressively smaller. But the risk from dangerous side-effects remains much the same.

Another reason for our modern diagnosis epidemic is the fact that we can see more inside the human body — thanks to high-tech machinery such as MRI scanners and CT scanners. They enable doctors to spot things that might be troublesome — even if they aren’t causing trouble and may very well never do so.

When investigators in three separate studies systematically scanned large numbers of healthy people, they found that about 10 per cent have gallstones, even though they have never had symptoms of gall bladder disease. Around 40 per cent show damaged knee cartilage, even though they have never had knee pain. And more than 50 per cent of people who have never had back pain show bulges in the discs in their spine when scanned by MRI.

In another test, in the journal Radiology, when 1,000 people were given total-body CT scans in commercial clinics, even though they had no problem symptoms, 86 per cent had at least one abnormality detected.

So if you go into hospital for broad-scale scanning tests, doctors are almost bound to find something problematic that needs ‘treatment’, even if it wasn’t what they were originally looking for — and even if it is, in fact, never going to cause problems.

The same sort of problem can occur with public-health campaigns such as Britain’s breast-screening programme. The potential dangers of overdiagnosis have even led the president of the Royal College of GPs, Iona Heath, to decline invitations to attend screening sessions.

Advocates of such screening say it prevents diseases, prompts early detection and saves lives — along with millions of pounds of NHS money. But as Dr Heath explains, a study of research evidence by the respected Cochrane Reviews Library ‘suggests that for every 2,000 women invited to screening for ten years, one death from breast cancer will be avoided but that ten women will be overdiagnosed with breast cancer’.

She adds: ‘This overdiagnosis is estimated to result in six extra tumour removals and four extra mastectomies and in 200 women risking significant psychological harm relating to the anxiety triggered by the further investigation of mammographic abnormalities.’

And now we’re entering new realms of disease-seeking, with the advent of DNA testing. Already, numerous commercial enterprises have emerged that will take your DNA and your money, promising to unlock the secrets of your genes.

But while DNA tests can reveal that you have a raised risk of developing one illness and a lower risk of another, ‘for the vast majority of conditions these predictions are inaccurate to the point of being meaningless’, says Dr Welch.

This is because our genes are not our destiny. Factors such as nutrition and harmful exposure to toxins affect human characteristics, even before birth, as does physical and even intellectual activity in childhood. ‘Virtually all of us will have genetic “abnormalities” if we look for them. So the new world of personal genetic testing has the potential to make all of us sick and arguably poses the greatest threat of overdiagnosis of all.’

Dr Welch is careful to say his scepticism is about testing for problems in people who are, to all intents and purposes, entirely well and free from any symptoms. ‘I am not saying that if you have early signs of symptoms of cancer, you shouldn’t go to your doctor,’ he explains.

‘The question is whether your doctor should be screening for cancers when you are well. It can hurt you. It can lead to you being overdiagnosed and treated needlessly.’

As for me, I’m going to stick to my everyday lifestyle — a vegetarian who exercises a lot — rather than start popping pills.

Where it is not bunk is when it shows that some treatment or influence has no effect on lifespan or disease incidence. It is as convincing as disproof as it is unconvincing as proof. Think about it. As Einstein said: No amount of experimentation can ever prove me right; a single experiment can prove me wrong.

Epidemiological studies are useful for hypothesis-generating or for hypothesis-testing of theories already examined in experimental work but they do not enable causative inferences by themselves

The standard of reasoning that one commonly finds in epidemiological journal articles is akin to the following false syllogism:
Chairs have legs
You have legs
So therefore you are a chair

I am rather in despair that important medical research is plagued by arrant nonsense. The simple truth that correlation is not causation seems unknown to most medical writers. As a last ditch attempt to get that truth into a few more skulls let me be "offensive". Offensiveness may serve to get the matter noticed. So here is the story: There is about a -.5 correlation between lip size and IQ. Big lips predict low IQ. Your run-of-the mill medical researcher will pounce on that as a huge breakthrough in finding the causes of IQ -- and propound new theories about things such as blood circulation to explain how lips affect IQ. But that is nonsense. Big lips are mostly found on people of African ancestry and, as all the studies attest, Africans are a very low IQ group. The correlation arises because of heredity, not lip size. There is a third factor behind the correlation -- and the possibility of such third factors seems to be a jaw-dropping surprise to most medical researchers

SALT -- SALT -- SALT

1). A good example of an epidemiological disproof concerns the dreaded salt (NaCl). We are constantly told that we eat too much salt for good health and must cut back our consumption of it. Yet there is one nation that consumes huge amounts of salt. So do they all die young there? Quite the reverse: Japan has the world's highest concentration of centenarians. Taste Japan's favourite sauce -- soy sauce -- if you want to understand Japanese salt consumption. It's almost solid salt.

2). We need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. So the conventional wisdom is not only wrong. It is positively harmful

3). Table salt is a major source of iodine, which is why salt is normally "iodized" by official decree. Cutting back salt consumption runs the risk of iodine deficiency, with its huge adverse health impacts -- goiter, mental retardation etc. GIVE YOUR BABY PLENTY OF SALTY FOODS -- unless you want to turn it into a cretin

4). Our blood has roughly the same concentration of salt as sea-water so claims that the body cannot handle high levels of salt were always absurd

5). The latest academic study shows that LOW salt in your blood is most likely to lead to heart attacks. See JAMA. 2011;305(17):1777-1785. More here and here and here for similar findings. Salt is harmless but a deficiency of it is not. We need it. See also here

PEANUTS: There is a vaccination against peanut allergy -- peanuts themselves. Give peanut products (e.g. peanut butter -- or the original "Bamba" if you have Israeli contacts) to your baby as soon as it begins to take solid foods and that should immunize it for life. See here and here (scroll down). It's also likely that a mother who eats peanuts while she is lactating may confer some protection on her baby. See here

THE SIDE-EFFECT MANIA. If a drug is shown to have troublesome side-effects, there are always calls for it to be banned or not authorized for use in the first place. But that is insane. ALL drugs have side effects. Even aspirin causes stomach bleeding, for instance -- and paracetamol (acetaminophen) can wreck your liver. If a drug has no side effects, it will have no main effects either. If you want a side-effect-free drug, take a homeopathic remedy. They're just water.

Although I am an atheist, I have never wavered from my view that the New Testament is the best guide to living and I still enjoy reading it. Here is what the apostle Paul says about vegetarians: "For one believeth that he may eat all things: another, who is weak, eateth herbs. Let not him that eateth despise him that eateth not; and let not him which eateth not judge him that eateth." (Romans 14: 2.3). What perfect advice! That is real tolerance: Very different from the dogmatism of the food freaks. Interesting that vegetarianism is such an old compulsion, though.

Even if we concede that getting fat shortens your life, what right has anybody got to question someone's decision to accept that tradeoff for themselves? Such a decision could be just one version of the old idea that it is best to have a short life but a merry one. Even the Bible is supportive of that thinking. See Ecclesiastes 8:15 and Isaiah 22: 13. To deny the right to make such a personal decision is plainly Fascistic.

Obesity does NOT causes diabetes. But insatiable eating is a prominent symptom of diabetes. So diabetes DOES cause obesity, which accounts for the correlation between the two things. The streets are full of fatties who don't have diabetes. How come? If conventional medical theory were correct we should be in the midst of an epidemic of diabetes. A recent high quality study has also found that fatties are LESS likely to die of diabetes

Elite people frequently express disapproval of red meat eating as a way of expressing their felt superiority to the ordinary people who eat it

IQ: Political correctness makes IQ generally unmentionable so it is rarely controlled for in epidemiological studies. This is extremely regrettable as it tends to vitiate findings that do not control for it. When it is examined, it is routinely found to have pervasive effects. We read, for instance, that "The mother's IQ was more highly predictive of breastfeeding status than were her race, education, age, poverty status, smoking, the home environment, or the child's birth weight or birth order". So political correctness can render otherwise interesting findings moot

"To kill an error is as good a service as, and sometimes better than, the establishing of a new truth or fact" -- Charles Darwin

"Most men die of their remedies, not of their diseases", said Moliere. That may no longer be true in general but there is still a lot of false medical "wisdom" around that does harm to various degrees -- the statin and antioxidant fads, for instance. And showing its falsity is rarely the problem. The problem is getting people -- medical researchers in particular -- to abandon their preconceptions

Bertrand Russell could have been talking about today's conventional dietary "wisdom" when he said: "The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd; indeed in view of the silliness of the majority of mankind, a widespread belief is more likely to be foolish than sensible.”

The challenge, as John Maynard Keynes knew, "lies not so much in developing new ideas as in escaping from old ones".

"Obesity" is 77% genetic. So trying to make fatties slim is punishing them for the way they were born. That sort of thing is furiously condemned in relation to homosexuals so why is it OK for fatties?

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Some more problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize dietary fat. But Eskimos living on their traditional diet eat huge amounts of fat with no apparent ill-effects. At any given age they in fact have an exceptionally LOW incidence of cardiovascular disease. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

11). A major cause of increasing obesity is certainly the campaign against it -- as dieting usually makes people FATTER. If there were any sincerity to the obesity warriors, they would ban all diet advertising and otherwise shut up about it. Re-authorizing now-banned school playground activities and school outings would help too. But it is so much easier to blame obesity on the evil "multinationals" than it is to blame it on your own restrictions on the natural activities of kids

12. Fascism: "What we should be doing is monitoring children from birth so we can detect any deviations from the norm at an early stage and action can be taken". Who said that? Joe Stalin? Adolf Hitler? Orwell's "Big Brother"? The Spanish Inquisition? Generalissimo Francisco Franco Bahamonde? None of those. It was Dr Colin Waine, chairman of Britain's National Obesity Forum. What a fine fellow!

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Trans fats: For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.

The "antioxidant" religion: The experimental evidence is that antioxidants SHORTEN your life, if anything. Studies here and here and here and here and here and here and here and here, for instance. That they are of benefit is a great theory but it is one that has been coshed by reality plenty of times.

The medical consensus is often wrong. The best known wrongheaded medical orthodoxy is that stomach ulcers could not be caused by bacteria because the stomach is so acidic. Disproof of that view first appeared in 1875 (Yes. 1875) but the falsity of the view was not widely recognized until 1990. Only heroic efforts finally overturned the consensus and led to a cure for stomach ulcers. See
here and here and here.

Dieticians are just modern-day witch-doctors. There is no undergirding in double-blind studies for their usual recommendations

The fragility of current medical wisdom: Would you believe that even Old Testament wisdom can sometimes trump medical wisdom? Note this quote: "Spiess discussed Swedish research on cardiac patients that compared Jehovah's Witnesses who refused blood transfusions to patients with similar disease progression during open-heart surgery. The research found those who refused transfusions had noticeably better survival rates.

Medical wisdom can in fact fly in the face of the known facts. How often do we hear reverent praise for the Mediterranean diet? Yet both Australians and Japanese live longer than Greeks and Italians, despite having very different diets. The traditional Australian diet is in fact about as opposite to the Mediterranean diet as you can get. The reverence for the Mediterranean diet can only be understood therefore as some sort of Anglo-Saxon cultural cringe. It is quite brainless. Why are not the Australian and Japanese diets extolled if health is the matter at issue?

Since many of my posts here make severe criticisms of medical research, I should perhaps point out that I am also a severe critic of much research in my own field of psychology. See here and here

This is NOT an "alternative medicine" site. Perhaps the only (weak) excuse for the poorly substantiated claims that often appear in the medical literature is the even poorer level of substantiation offered in the "alternative" literature.

I used to teach social statistics in a major Australian university and I find medical statistics pretty obfuscatory. They seem uniformly designed to make mountains out of molehills. Many times in the academic literature I have excoriated my colleagues in psychology and sociology for going ga-ga over very weak correlations but what I find in the medical literature makes the findings in the social sciences look positively muscular. In fact, medical findings are almost never reported as correlations -- because to do so would exhibit how laughably trivial they generally are. If (say) 3 individuals in a thousand in a control group had some sort of an adverse outcome versus 4 out of a thousand in a group undergoing some treatment, the difference will be published in the medical literature with great excitement and intimations of its importance. In fact, of course, such small differences are almost certainly random noise and are in any rational calculus unimportant. And statistical significance is little help in determining the importance of a finding. Statistical significance simply tells you that the result was unlikely to be an effect of small sample size. But a statistically significant difference could have been due to any number of other randomly-present factors.

"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correlation coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic conditions and lynchings in Raper's data. Raper had the misfortune of stopping his analysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."

So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.

The Truth About Ancel Keys. Keys was a brilliant man but his concentration on heart disease misled him. He was right that high fat intake predicted high rates of heart disease (though it was ANIMAL fat in particular that was the "culprit") but he overlooked that the same intake predicted LESS mortality from other causes. The same narrow vision led him to be the earliest prominent advocate of the "Mediterranean diet" hypothesis. It's true that Mediterraneans have less heart disease but they have more of other causes of death, so that Mediterranean countries do not have particularly long lifespans when compared with other developed countries. If there are any lessons about diet to be learned from lifespans, it is un-Mediterranean countries like Australia and the Nordic countries that one should look to.

The intellectual Roman Emperor Marcus Aurelius (AD 121-180) could have been speaking of the prevailing health "wisdom" of today when he said: "The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane."

Improbable events do happen at random -- as mathematician John Brignell notes rather tartly: "Consider, instead, my experiences in the village pub swindle. It is based on the weekly bonus ball in the National Lottery. It so happens that my birth date is 13, so that is the number I always choose. With a few occasional absences abroad I have paid my pound every week for a year and a half, but have never won. Some of my neighbours win frequently; one in three consecutive weeks. Furthermore, I always put in a pound for my wife for her birth date, which is 11. She has never won either. The probability of neither of these numbers coming up in that period is less than 5%, which for an epidemiologist is significant enough to publish a paper.

Kids are not shy anymore. They are "autistic". Autism is a real problem but the rise in its incidence seems likely to be the product of overdiagnosis -- the now common tendency to medicalize almost all problems.

One of the great pleasures in life is the first mouthful of cold beer on a hot day -- and the food Puritans can stick that wherever they like

NOTE: The archives provided by blogspot below are rather inconvenient. They break each month up into small bits. If you want to scan whole months at a time, the backup archives will suit better. See here or here